This group studies how organisms sense environmental signals and transduce the signals into changes in gene expression and cell physiology. The group has continued their characterization of the two regulators central to the Escherichia coli response to oxidative stress: OxyR, a 34 kDa transcriptional regulator whose activity is modulated by oxidation and reduction, and OxyS, a novel 109 nucleotide RNA that acts as an activator and repressor of gene expression. In addition to studying the mechanism of OxyS RNA action, the group has begun to characterize the functions of other small, untranslated RNAs in E. coli. The group recently discovered that the 6S RNA associates with and modulates RNA polymerase. The group also has carried out genetic screens and whole genome expression analysis to determine what regulators are important to the Saccharomyces cerevisiae response to hydrogen peroxide.